A rate-dependent cohesive zone model with the effects of interfacial viscoelasticity and progressive damage

A generalized rate-dependent cohesive zone model for describing the interfacial viscoelasticity and progressive damage of mode I fracture is presented. The proposed model has efficiently extended the traditional bi-linear cohesive traction-separation law to remove the assumptions that some of the rate-dependent parameters such as elastic stiffness, initial separation and strength, critical separation are constant at different loading speeds. Furthermore, the ratedependency of the damage evolution, which is observed in experiments but largely neglected in the previous models, is established to describe the rate-dependent fracture process linked with the generalized traction-separation law, and an equivalent generalized Maxwell model (GMM), based on the Kohlrausch-William-Watts function with significant fewer material parameters required as input, is proposed to describe the time and history dependent stress-strain relationship of the viscoelastic interface material. The proposed model is validated by the simulations of the DCB tests with both the SBR/NR rubber interface and Polyurethane interface.